The present invention relates to a tire/wheel assembly and a run-flat support member. More specifically, the present invention relates to a tire/wheel assembly and a run-flat support member used therefore, in which durability can be improved.
In response to demands in the market, there have been many technologies proposed to allow a vehicle to run urgently in the order of several hundreds of kilometers even when a pneumatic tire is punctured while the vehicle is running. Among these many proposals, those proposed in Japanese Patent Laid-Open Publication No. 10-297226 and Published Japanese Translation of a PCT Application No. 2001-519279 have enabled run-flat traveling by fitting a support member onto a rim inside a cavity of a pneumatic tire assembled to the rim and supporting the punctured tire using the support member.
The preceding run-flat support member includes a circular shell in which the outer circumferential side thereof is a support surface and an inner circumferential side thereof is opened so as to form two leg portions. Also, elastic rings are fitted to both leg portions of the circular shell, thus the run-flat support member is supported on the rim via the elastic ring. In this run-flat support member, a conventional wheel and rim can be used as they are without any special modifications. Therefore, the run-flat support member is advantageously adopted without causing confusions in the market.
However, considering the structure of this type of run-flat support member, the elastic rings are vulnerable to damage in comparison with the circular shell during run-flat traveling. Therefore, durability of the run-flat support member depends largely on durability of the elastic rings. Hence, in order to improve durability of the tire/wheel assembly to which the above run-flat support member is attached during run-flat traveling, an improvement of the elastic rings' durability is vital.